1. Technical Field
Aspects of this document relate generally to permanent magnet synchronous motors. More specific implementations involve rotor position detection of permanent magnet synchronous motors.
2. Background
Torque in a permanent magnet synchronous motor is created by applying out of phase currents to the stator or field windings of the motor. The out of phase currents create a magnetic flux in the motor which results in the rotation of a magnetic rotor. The amount of torque is controlled by the out of phase currents applied and the position of the magnetic rotor. Various conventional position sensing systems for permanent magnet synchronous motors are disclosed in U.S. Patent Application Publication No. 2010/0181952 to Kuang-Yao Cheng, entitled “Initial rotor position detection for permanent magnet synchronous motors,” published Jul. 22, 2010 and in U.S. Pat. No. 5,028,852 to John C. Dunfield entitled “Position detection for a brushless DC motor without hall effect devices using a time differential method,” issued Jul. 2, 1991, the disclosures of each of which are hereby incorporated entirely herein by reference.